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App55 client library for the Java platform.
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/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

package com.googlecode.openbeans.beancontext;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;

import org.apache.harmony.beans.internal.nls.Messages;

import com.googlecode.openbeans.PropertyChangeEvent;
import com.googlecode.openbeans.PropertyChangeListener;
import com.googlecode.openbeans.PropertyChangeSupport;
import com.googlecode.openbeans.PropertyVetoException;
import com.googlecode.openbeans.VetoableChangeListener;
import com.googlecode.openbeans.VetoableChangeSupport;

public class BeanContextChildSupport implements BeanContextChild, BeanContextServicesListener, Serializable
{

	private static final long		serialVersionUID	= 6328947014421475877L;

	static final String				BEAN_CONTEXT		= "beanContext";		//$NON-NLS-1$

	protected transient BeanContext	beanContext;

	public BeanContextChild			beanContextChildPeer;

	protected PropertyChangeSupport	pcSupport;

	protected transient boolean		rejectedSetBCOnce;

	protected VetoableChangeSupport	vcSupport;

	private transient BeanContext	lastVetoedContext;

	public BeanContextChildSupport()
	{
		// This class implements the JavaBean component itself
		this(null);
	}

	public BeanContextChildSupport(BeanContextChild bcc)
	{
		// If 'bcc' parameter is not null the JavaBean component itself
		// implements BeanContextChild
		this.beanContextChildPeer = (bcc == null ? this : bcc);

		// Initialize necessary fields for later use
		pcSupport = new PropertyChangeSupport(this.beanContextChildPeer);
		vcSupport = new VetoableChangeSupport(this.beanContextChildPeer);
		this.rejectedSetBCOnce = false;
	}

	public void addPropertyChangeListener(String name, PropertyChangeListener pcl)
	{
		// Do nothing if name or listener is null
		if ((name == null) || (pcl == null))
		{
			return;
		}

		this.pcSupport.addPropertyChangeListener(name, pcl);
	}

	public void addVetoableChangeListener(String name, VetoableChangeListener vcl)
	{
		// Do nothing if name or listener is null
		if ((name == null) || (vcl == null))
		{
			return;
		}

		this.vcSupport.addVetoableChangeListener(name, vcl);
		this.lastVetoedContext = null;
	}

	public void firePropertyChange(String name, Object oldValue, Object newValue)
	{
		this.pcSupport.firePropertyChange(name, oldValue, newValue);
	}

	public void fireVetoableChange(String name, Object oldValue, Object newValue) throws PropertyVetoException
	{

		this.vcSupport.fireVetoableChange(name, oldValue, newValue);
	}

	public synchronized BeanContext getBeanContext()
	{
		return this.beanContext;
	}

	public BeanContextChild getBeanContextChildPeer()
	{
		return this.beanContextChildPeer;
	}

	protected void initializeBeanContextResources()
	{
	}

	public boolean isDelegated()
	{
		return (!this.beanContextChildPeer.equals(this));
	}

	private void readObject(ObjectInputStream ois) throws IOException, ClassNotFoundException
	{

		ois.defaultReadObject();
	}

	protected void releaseBeanContextResources()
	{
	}

	public void removePropertyChangeListener(String name, PropertyChangeListener pcl)
	{

		this.pcSupport.removePropertyChangeListener(name, pcl);
	}

	public void removeVetoableChangeListener(String name, VetoableChangeListener vcl)
	{

		this.vcSupport.removeVetoableChangeListener(name, vcl);
		this.lastVetoedContext = null;
	}

	public void serviceAvailable(BeanContextServiceAvailableEvent bcsae)
	{
		if (isDelegated())
		{
			((BeanContextServicesListener) beanContextChildPeer).serviceAvailable(bcsae);
		}
	}

	public void serviceRevoked(BeanContextServiceRevokedEvent bcsre)
	{
		if (isDelegated())
		{
			((BeanContextServicesListener) beanContextChildPeer).serviceRevoked(bcsre);
		}
	}

	public synchronized void setBeanContext(BeanContext bc) throws PropertyVetoException
	{

		// Do nothing if the old and new values are equal
		if ((this.beanContext == null) && (bc == null))
		{
			return;
		}

		if ((this.beanContext != null) && this.beanContext.equals(bc))
		{
			return;
		}

		// Children are not allowed to repeatedly veto this operation.
		// So, we set rejectedSetBCOnce flag to true if veto occurs
		// and never veto the change again
		if (!(this.rejectedSetBCOnce && this.lastVetoedContext == bc))
		{
			this.lastVetoedContext = bc;
			this.rejectedSetBCOnce = true;
			// Validate the new BeanContext value and throw
			// PropertyVetoException if it was not successful
			if (!validatePendingSetBeanContext(bc))
			{
				throw new PropertyVetoException(Messages.getString("beans.0F"), //$NON-NLS-1$
						new PropertyChangeEvent(this.beanContextChildPeer, BEAN_CONTEXT, this.beanContext, bc));
			}
			fireVetoableChange(BEAN_CONTEXT, this.beanContext, bc);
		}

		this.rejectedSetBCOnce = false;

		releaseBeanContextResources();

		// We have to notify all listeners about "beanContext"
		// property change
		firePropertyChange(BEAN_CONTEXT, this.beanContext, bc);
		this.beanContext = bc;
		initializeBeanContextResources();
		// }
	}

	public boolean validatePendingSetBeanContext(BeanContext newValue)
	{
		return true;
	}

	private void writeObject(ObjectOutputStream oos) throws IOException
	{
		oos.defaultWriteObject();
	}
}